<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<h1>注册</h1>
<div>

  <input type="text" placeholder="用户名"  @blur="f()" v-model="user.username">{{info}}<br>
  <input type="password" placeholder="密码" v-model="user.password"><br>
  <input type="text" placeholder="昵称" v-model="user.nickname"><br>
  <input type="button" value="注册" @click="reg()">
</div>
<script src="https://cdn.bootcdn.net/ajax/libs/axios/0.21.1/axios.min.js"></script>
 <script src="https://cdn.staticfile.org/vue/2.2.2/vue.min.js"></script>
     <script>
         let v = new Vue({
             el:"body>div",
             data:{
                 info:"",
                 user:{
                   username:"",
                   password:"",
                   nickname:""
                 }
             },
             methods:{
                 reg(){
                   axios.post("/reg",v.user).then(function (response) {
                     if(response.data=1){
                         alert("注册成功")
                         location.href="/";
                     }else {
                         alert("已存在")
                     }
                   })
                 },
                 f(){
                     axios.post("/reg",v.user).then(function (response) {
                         if(response.data==2){
                             v.info="用户已存在"
                         }else {
                             v.info="合法";
                         }


                     })
                 }
             }

         })
     </script>
</body>
</html>